A challenge by Graham Dwyer to the legality of the use of mobile phone data that was key to his conviction for the murder of Elaine O'Hara has become entangled in a broader power struggle between European governments and the bloc's highest court.
Lawyers for 14 member states have made submissions for the consideration of the European Court of Justice in Luxembourg, which bundled the Dwyer case together with two German cases in a single hearing on Monday as they concern the same points of law.
Arguments advanced by various EU member states made it clear that several capitals are deeply concerned about the potential impact on law enforcement efforts if the court upholds a more restrictive interpretation of how authorities can retain and access data.
In October 2020 the European Court of Justice found that EU law did not permit national authorities to conduct “indiscriminate transmission or retention of traffic data and location data for the purpose of combating crime in general or of safeguarding national security”, as the court described it in a press release.
Authorities can only order telecom companies to temporarily retain all mobile phone metadata – such as the times and numbers of calls and texts – if governments are facing a specific, imminent and serious threat to national security, the court found.
The data of suspected terrorists can be monitored – subject to the prior review of a court or formal body – but authorities can otherwise only carry out time-limited “targeted retention” of such data, which is limited according to geographical location, time period, and “categories of persons concerned”.
But on Monday a series of lawyers representing EU member states argued against this previous case law, insisting such constraints would make the combatting of serious crime all but impossible in the digital age.
Sweden’s Hanna Shev warned that such restrictions would mean “in practice internet crime could be committed with impunity”, while Poland’s Jana Sawicka warned that the kind of precision asked for was impractical because “at the stage of retention it is not possible to foresee which data will be needed to solve crimes”.
In the case of Dwyer, data from two mobile phones were crucial to identifying him as a suspect, meaning that the data was accessed before the Foxrock architect was ever under suspicion - something his lawyers say amounts to indiscriminate retention of data.
Lawyers for France and the Netherlands described the case as a clear illustration of how restricting data retention in the way the court has previously set out would hamper vital police work.
Tanguy Stéhelin for France said the Dwyer case showed the “tragic consequences” that such restrictions could have, and argued against a distinction between serious crime and national security, noting that areas like drug and people trafficking showed they were deeply entwined.
“If we don’t have efficient tools to ensure security and justice within member states, we are putting at threat fundamental freedoms and at the end of the day, democracy,” Stéhelin said.
He concluded with a warning echoing that of Ireland’s attorney general Paul Gallagher: that a judgement favourable to Dwyer’s case could undermine public confidence and therefore, the authority of the court.